It has the usual solid, key information that the Ugly’s book has, however UglysElectricalReferences functionality is terrible in three key respects. One, the search function is so basic that it’s almost completely useless. NEC article number references won’t show up in search results, as well as any number of other basic key words and table titles. A pdf document is more searchable, never mind that a book index would contain more “searchable”information. Two, the bookmarks function doesn’t work at all...if I bookmark a page, when I go back to the bookmark... it takes me to the wrong page every time, even though the title of the bookmark is correct. It’s very frustrating!...Especially for something that is not free. And three, sometimes when I scroll through a section, UglysElectricalReferences will ”glitch” and send me to a completely different section with no way to get back to the section that I was originally looking at without going back through the menu titles and subsections and re-selecting my original page. I’m not sure why UglysElectricalReferences lacks the basic functionality that it itself indicates that it is capable of handling. My version utilizes the latest update. What’s the point of buying UglysElectricalReferences if it doesn’t even work as advertised. I don’t know that I would buy UglysElectricalReferences if I could go back...it’s failure to work as advertised makes it a hard sell over just getting the book.